NEW YORK (Reuters) - The Reverend Al Sharpton led thousands of chanting but peaceful activists in a march across Staten Island on Saturday to protest the death of Eric Garner, who died after New York City police put him in a banned chokehold last month.

Protesters traveled by bus and ferry to join the rally over Garner, a 43-year-old black father of six, whose killing has become part of a larger national debate about how U.S. police use force, particularly on people who are not white.

"If you can do it to him, then you can do it to any citizen and we are not going to be silent when that happens," Sharpton said at a pre-rally speech at the Mt. Sinai United Christian Church in the borough where Garner died.

Sharpton was joined by former New York Governor David Patterson, other civil rights leaders and Garner's widow, Esaw.

"Let's make this a peaceful march and get justice for my husband so that this doesn't happen to anybody else," Esaw Garner said in a somber tone to protesters.

The demonstration was also in response to the death of Michael Brown, an unarmed 18-year-old African American who was shot dead by a white police officer this month in Ferguson, Missouri, sparking more than a week of violent confrontations, Sharpton said.

Protesters carried signs asking for justice for Garner and Brown and shouted slogans including, "Hands up don't shoot." They began Saturday's march at just after noon, with plans to walk past the District Attorney's Office, a few blocks from the terminal for ferries to Manhattan.

Dawn Edwards, a human resource executive from Brooklyn, said she chose to march out of fear that negative stereotypes will have an impact on her two young sons as they grew older.

"I hope when my boys grow up to become men those stereotypes will no longer exist," she said.

A few dozen New York Police Department officers lined blocked streets near the march's starting point.

A New York City prosecutor said on Tuesday that he will present evidence to a grand jury next month to determine whether anyone should be criminally charged in Garner's death.

The city's medical examiner ruled the death a homicide, saying police officers killed him by compressing his neck and chest as they restrained him for selling loose cigarettes. His health problems, including asthma and obesity, were contributing factors, the medical examiner said.